debugger: don't queue -exec-interrupt

Change-Id: I65da52375872552064ffa4fa9db8292d27f64f67
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: hjk <qthjk@ovi.com>

src/plugins/debugger/gdb/gdbengine.cpp

@@ -718,7 +718,7 @@ void GdbEngine::interruptInferior()
         qDebug() << "INTERRUPT INFERIOR: " << state(); return);
 
     if (usesExecInterrupt()) {
-        postCommand("-exec-interrupt");
+        postCommand("-exec-interrupt", Immediate);
     } else {
         showStatusMessage(tr("Stop requested..."), 5000);
         showMessage(_("TRYING TO INTERRUPT INFERIOR"));